In the PC field, a plurality of displays are combined to form a larger display desktop, so as to provide many conveniences to a user, especially during occasions such as data analysis and conferences, to facilitate simultaneous display of a plurality of data. An existing notebook or PC is generally provided with one external display interface. However, one external display cannot satisfy these requirements. On the other hand, an external docking device connected via a USB or UWB connection has become an important peripheral in the computer industry. The core function of the docking device is a video function. As USB and UWB can conveniently be connected with a plurality of devices, it has become a new application mode in the field of multi-display to form a larger desktop by connecting a plurality of docking devices. In some configurations, other docking functions can even be removed while the video function remains.
Multi-display can be supported by simply combining a plurality of external docking devices. However, as the order in which the user sequentially inserts the docking connections may be different, it is necessary to rearrange the order of the displays each time they are used, which causes inconvenience. In another common occasion, these external docking devices may be connected to each other by one USB hub or UWB hub. In such a case, the user only has to connect the hub once in order to connect to all of the external docking devices. Even in this case, the order in which the USB enumerates devices may change. Thus, the same problem still exists as the order in which the host enumerates devices after the devices are connected remains different.
Additionally, in other fields such as audio, there is also a need for an output system capable of restoring the arrangement of the devices (e.g., a plurality of speakers with stereo effect which are commonly used in today's home cinema).